KR20180013899A - Nonwoven fabric for absorbent articles - Google Patents

Abstract

An object of the present invention is to obtain a nonwoven fabric for an absorbent article which can obtain a delicate, smooth and smooth touch when a finger touches. That is to say, the nonwoven fabric 1 for absorbent articles has a plurality of convex portions 4 and a plurality of concave portions 11 in a plurality of groove portions 5 formed in a space between adjacent convex portions 4, The first bottom part 12 is provided with the second concave part 16 having the second bottom part 18 formed in a recessed shape opened to the first bottom part 12 and the convex part The distance between the top 4a of the convex portion 4 of the nonwoven fabric 1 and the top 4a of the convex portion 4 adjacent to the convex portion 4 is 0.5 to 2 mm, 4) is 10 to 30 mu m.

Description

Nonwoven fabric for absorbent articles

The present invention relates to a nonwoven fabric used for an absorbent article such as a disposable diaper, a sanitary napkin, and a urinary incontinence pad.

For example, in an absorbent article such as a disposable diaper, a nonwoven fabric used as a constituent member of a topsheet or the like is a portion that touches the skin of a user, and therefore, it is a large condition that is flexible and has good touch.

For this reason, in recent years, a nonwoven fabric having a convex portion in a plurality of rows and a groove portion formed in a space between adjacent convex portions is often used on the surface contacting the skin, but such a nonwoven fabric has a relatively flexible convex portion The convex portion tends to fit on the skin surface, so that the flexibility of the nonwoven fabric tends to be easily felt.

Among the nonwoven fabrics of this type, in order to further improve the tactile feel by the delicate and soft touch, for example, as described in Patent Document 1, a small convex portion of an island shape smaller than the convex portion is formed on the surface of the convex portion of the arcuate shape . In the nonwoven fabric described in Patent Document 1, by making the contact area of the nonwoven fabric with the skin small by the small convex portion, it is easy to feel fresh sensation and smoothness when the nonwoven fabric touches, thereby improving the feel.

Patent Document 1: Japanese Patent Application Laid-Open No. 2005-334374

However, in the nonwoven fabric described in Patent Document 1, the tactile feel is improved as compared with the case where there is no small convex portion due to the reduced contact area of the nonwoven fabric to the skin. However, when the skin slips on the surface of the nonwoven fabric, Since irregularities due to the presence of convex portions may leave a dry and irritating texture on the surface of the nonwoven fabric, there is a possibility that it may not be attained to obtain a delicate, smooth and skin-like feeling.

A technical object of the present invention is to provide a nonwoven fabric for an absorbent article which can obtain a delicate, smooth and skin-like feeling when a finger touches.

A nonwoven fabric for an absorbent article of the present invention for solving the above problems is as follows.

(1) a plurality of convex portions having a first surface and a second surface opposite to the first surface, the convex portions protruding from the second surface toward the first surface, and A nonwoven fabric for absorbent articles comprising thermoplastic resin fibers, the nonwoven fabric comprising a plurality of recesses recessed toward the surface of the nonwoven fabric, wherein the protrusions extend toward the first direction in the plane direction of the nonwoven fabric, Wherein the recesses are formed at predetermined intervals in a second direction orthogonal to the first direction in the plane direction of the nonwoven fabric, and the groove portions are arranged in a space between the convex portions adjacent to each other in the second direction toward the first direction A first concave portion extending from a top of the convex portion and having a first bottom portion located in a direction of a second surface than a position of the first surface in the top portion of the convex portion; And a second bottom portion that is discontinuously formed in the first direction and formed in a recessed shape that is open to the first bottom portion, the second bottom portion being positioned in the direction of the second surface than the first bottom portion , The distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion is 0.5 to 2 mm and the average fiber diameter of the fibers forming at least the convex portion in the nonwoven fabric is 10 to 30 mu m Nonwoven fabric for absorbent articles.

(2) The nonwoven fabric for an absorbent article as described in (1) above, wherein the fiber forming the convex portion has an average fiber-to-fiber distance of 50 to 150 m.

As a result, the fibers forming the convex portions tend to follow the irregularities of the fingerprint, so that the fibers forming the convex portions can enter the spaces between the protruding portions more stably, and a moist feeling tending to be easily wrapped around the skin can be obtained.

(3) The second concave portion has a peripheral wall portion extending from the first bottom portion in a direction opposite to the protruding direction of the convex portion, and the end portion of the peripheral wall portion in the direction opposite to the first bottom portion (1) or (2), wherein the second bottom portion is formed so as to close the end portion thereof.

As a result, the contact area of the first bottom portion of the first concave portion with respect to the skin can be more stably suppressed, and a flexible touch can be provided. Further, since the second bottom portion is located at a position away from the convex portion by the peripheral wall portion, when the skin touches the first surface, the second bottom portion is hard to come into contact with the skin, The touch can be ensured.

(4) The peripheral wall portion of the second concave portion has a pair of first peripheral wall portions formed along the first direction and a pair of second peripheral wall portions formed along the second direction, The nonwoven fabric for an absorbent article according to (3), wherein the wall portion has a hole portion passing through between the first surface and the second surface.

Thus, the hole portion of the first peripheral wall portion of the peripheral wall portion releases the tensile force of the fibers forming the adjacent convex portions, so that the degree of freedom of moving the entirety of the convex portion or the fibers forming the convex portion can be improved . As a result, not only the flexibility of the convex portion can be further improved, but also the fibers of the convex portion can be easily followed to the irregularities of the fingerprint, so that a delicate, soft and easily touched feeling can be stably obtained.

(5) The hole portion has the peripheral edge portion formed without melting the thermoplastic resin fiber, and the peripheral edge portion includes the break end portion of the broken fiber having the break end portion formed by the fracture of the thermoplastic resin fiber (4). ≪ / RTI >

Accordingly, even if the skin touches the peripheral edge portion of the hole portion, since there is no thermoplastic resin fiber that is hardened by melting in the peripheral edge portion, discomfort due to stretching or fiber sticking is suppressed, It is suppressed to feel hardness or roughness.

(6) The nonwoven fabric for an absorbent article as described in (4) or (5) above, wherein the hole portion has a part of the thermoplastic resin fiber in an inner space of the hole portion.

Thus, even if the skin touches the hole, the thermoplastic resin fiber in the inner space can reduce the boundary or step between the first peripheral wall portion of the second concave portion and the second bottom portion and the hole portion. Thus, even if there is a hole portion, a smooth touch can be maintained, so that it is possible to reduce discomfort when touching due to the presence of the hole portion.

(7) The nonwoven fabric for an absorbent article as described in any one of (4) to (6), wherein the hole portion has an opening ratio of 1 to 50% in the inner space.

As a result, flexibility can be ensured by imparting an appropriate degree of freedom to the fibers of the convex portion and the convex portion, while securing the strength of the first peripheral wall portion in which the hole portion is formed, and also providing a feeling of discomfort when touching the circumferential edge portion of the hole portion .

(8) The nonwoven fabric for an absorbent article according to any one of (4) to (7), wherein the hole is formed only at a position near the second bottom portion of the first peripheral wall portion.

As a result, the hole portion can be made as far as possible from the convex portion or the first bottom portion, which is likely to come in contact with the skin, so that the chance that the hole portion touches the skin can be minimized and the uncomfortable feeling or foreign matter caused by the hole portion can be reduced. As a result, the smoothness when the skin slides in the plane direction of the nonwoven fabric can be more stably secured.

(9) The second concave portion may be formed in any one of (1) to (8), wherein the distance from the first surface of the first bottom portion to the first surface of the second bottom portion in the first concave portion is 0.05 to 2 mm The nonwoven fabric for an absorbent article according to any one of the preceding claims.

Accordingly, it is possible to secure the fiber density at the time of forming the second bottom portion, to suppress the lowering of the rigidity of the second bottom portion, to secure the rigidity of the peripheral wall portion of the second recess portion, and to secure the strength of the entire nonwoven fabric .

According to the present invention, since the average fiber diameter of the fibers forming the convex portions is smaller than the width between the protruding portions of the finger fingerprint and the distance between the top portions of the adjacent convex portions is set within a predetermined range, The fibers tend to follow the irregularities of the fingerprint of the fingerprint, and the fibers forming the convex portions are likely to enter between the projections. On the other hand, by the presence of the second concave portion, the area of the first concave portion that is in contact with the skin is suppressed, and a flexible touch can be obtained. As a result, not only the soft touch of the nonwoven fabric as a whole can be obtained, but also the fibers forming the convex portions stimulate the tactile organs on the flat portions or the side portions of the projections between the adjacent projections of the fingerprint, So that a moist texture can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partially broken perspective view schematically showing an embodiment of a nonwoven fabric for an absorbent article according to the present invention. Fig.
2 is a plan view schematically showing an embodiment of a nonwoven fabric for an absorbent article according to the present invention.
3 is an enlarged cross-sectional view of the main part taken along line AA in Fig.
Fig. 4A is a diagram schematically showing a fingerprint fingerprint, and Fig. 4B is a cross-sectional view for explaining a state in which the fibers forming the convex portion of the nonwoven fabric for absorbent article according to the present invention are in contact with the fingerprint.
5 is a view schematically showing an example of a manufacturing apparatus for producing a nonwoven fabric for an absorbent article according to the present invention.
6 is an enlarged perspective view of a main part schematically showing a pair of stretching rolls of a shaping apparatus.
7 is an enlarged view of a main part schematically showing the arrangement of the pins of the lower stretching roll.
8 is an enlarged view of a main portion showing a state in which an upper stretching roll and a lower stretching roll are engaged with each other.

1 to 3 illustrate an embodiment of the nonwoven fabric for an absorbent article of the present invention. The nonwoven fabric 1 of this embodiment has a first face 2 and a second face 2 opposite to the first face 2 A plurality of convex portions 4 protruding toward the first surface 2 side (upper side in Figs. 1 to 3) and a second convex portion 4 having a second surface 3 of the second surface 3, And a plurality of grooves 5 recessed in a direction opposite to the projecting direction of the sheet 4 (downward in Figs. 1 to 3). The nonwoven fabric 1 has a first direction X in the plane direction of the nonwoven fabric 1 and a second direction Y perpendicular to the first direction X in the plane direction of the nonwoven fabric 1. [ Lt; / RTI >

In this embodiment, the direction in which the convex portion 4 protrudes is referred to as the upper side, and the direction opposite to the direction in which the convex portion protrudes is referred to as the lower side.

The nonwoven fabric of the present invention is suitably used as a topsheet or leak-barrier wall of an absorbent article such as a disposable diaper, a sanitary napkin, a urinary pad, a panty liner, or the like, i.e., a sheet disposed on the side of the absorbent article in contact with the user's skin. Or as a sheet adhered to the outer surface of a back sheet of a disposable diaper or the like.

When the nonwoven fabric of the present invention is used for an absorbent article, the second surface of the nonwoven fabric is bonded to each constituent member of the absorbent article (for example, an absorber when used as a topsheet). At this time, it is highly desirable that the second surface side of the convex portion (particularly, the top portion) is not bonded.

In the present invention, examples of the thermoplastic resin constituting the thermoplastic resin fibers contained in the nonwoven fabric include polyolefins, polyesters, and polyamides. Examples of the polyolefin include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), polypropylene, polybutylene, Vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA), ethylene-acrylic acid copolymer (EAA), and ionomer resin). Examples of the polyester include linear or branched poly (ethylene terephthalate) (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), polylactic acid and polyglycolic acid. Polyesters such as polyhydroxyalkanoic acids, copolymers mainly composed of these, and copolyesters composed mainly of alkylene terephthalate and copolymerized with other components in a small amount. Examples of polyamides include 6-nylon and 6,6-nylon. The fiber length is usually 20 to 100 mm, preferably 35 to 65 mm. The hydrophilic treatment may be performed on the thermoplastic resin fiber. The hydrophilization treatment may be carried out, for example, by a treatment using a surfactant, a hydrophilic agent, etc. (for example, by adding a surfactant to the inside of the fiber, And the like), and the like.

In addition to the thermoplastic resin fibers, the nonwoven fabric of the present invention may contain other constituent fibers. Examples of the other constituent fibers include natural fibers (e.g., wool, cotton), regenerated fibers (e.g., rayon and acetate), and inorganic fibers (such as glass fiber and carbon fiber). Also, the nonwoven fabric may include composite fibers such as core / sheath type fibers, side by side type fibers, and island / sea type fibers; Hollow type fibers; Deformed fibers such as flattened, Y-shaped, and C-shaped; Potential crimp or current crimp fiber; Split fibers that are divided by physical loads such as water flow, heat, and embossing may be mixed.

The nonwoven fabric 1 is formed by folding the sheet-like nonwoven fabric before being processed into the direction of the first surface 2 side and the direction of the second surface 3 side, that is, by alternately folding the upper side and the lower side The plurality of convex portions 4 described above are formed by the portion folded toward the first surface 2 side, that is, toward the upper side, and the convex portions 4 are formed in the direction opposite to the direction in which the convex portions 4 protrude That is, the portions folded toward the lower side are formed.

The convex portion 4 is formed so as to extend continuously in the first direction X in the plane direction (sheet surface) of the nonwoven fabric 1 and a plurality of convex portions 4 are formed at a predetermined interval in the second direction Y Is formed. In this embodiment, each of the convex portions 4 is formed so as to extend continuously in the first direction X and to be substantially parallel to the other convex portions 4. [

On the other hand, the groove 5 is formed to extend in the first direction X in a space between adjacent convex portions 4, 4 in the second direction Y.

The groove 5 is formed so as to extend in the direction of the second surface 3 from the position of the first surface 2 at the apex 4a of the convex portion 4, (11) having a first recess (11) formed discontinuously in the first direction (X) in the first recess (11) and having a recess 2 concave portion 16 as shown in Fig.

The first concave portion 11 is formed integrally with the convex portion 4 in the second direction Y. [ The thickness of the maximum portion of the first bottom portion 12 of the first concave portion 11 (maximum distance between the first surface 2 and the second surface 3) And the first bottom portion 12 is entirely made of a portion having excellent elasticity. The plurality of first concave portions 11 formed in the nonwoven fabric 1 are all formed to have the same width.

The second concave portion 16 has an approximately rectangular opening when viewed in a plan view (in this embodiment, viewed from above) and protrudes as a whole downward of the nonwoven fabric 1 to form an approximately rectangular parallelepiped inner space Respectively. The second concave portions 16 are arranged at regular intervals in the first direction X of the respective groove portions 5 and more concretely in the first direction X of the first concave portion 11, Each of the second concave portions 16 is formed so as to be independent from the other second concave portions 16.

The second concave portion 16 is provided with a raised wall-shaped circumferential wall portion 17 (not shown) formed to extend downward in the direction opposite to the direction in which the convex portion 4 protrudes from the first bottom portion 12 And a second bottom surface 12 which is formed so as to cover an end portion of the peripheral wall portion 17 opposite to the first bottom portion 12 on the side opposite to the first bottom portion 12, , I.e., the second bottom portion 18 located on the lower side.

The second bottom portion 18 is formed by compressing the fibers constituting the nonwoven fabric 1 in the up-and-down direction. The nonwoven fabric 1 has the highest fiber density and the highest stiffness.

The first surface 2 (that is, the surface on the inner side of the second concave portion 16) and the second surface 3 of the second bottom portion 18 are formed in a substantially planar shape as a whole .

Here, in the present invention, the second recess is formed in the nonwoven fabric to minimize the possibility that the bottom of the groove, more specifically the first bottom of the first recess, comes into contact with the skin, So that the contact area can be minimized.

That is, when the nonwoven fabric according to the present invention is used, for example, as a top sheet for an absorbent article, the second surface of the nonwoven fabric is bonded to the absorbent article of the absorbent article. In this state, 1 It is easy to touch skin in order of bottom part. At this time, since the convex portion (particularly the top portion) is hardly bonded to the absorbent body and has high flexibility, it is preferable that the convex portion is more likely to touch the skin than the first bottom portion. On the other hand, as the nonwoven fabric used for the topsheet and the like, the flexibility of the nonwoven fabric tends to be felt when the contact area of the nonwoven fabric as a whole is small.

Therefore, in the present invention, by forming the second concave portion and forming the portion where the first bottom portion does not exist, the portion of the first bottom portion of the first concave portion that is in contact with the skin is made smaller, 1, the contact with the bottom part is minimized as much as possible, and the contact area is made as small as possible even when the skin contacts the first bottom part.

The second concave portion is formed on the first bottom portion because the second concave portion is formed on the first bottom portion of the first concave portion which is harder to reach the skin than the convex portion, So that the chance of the second concave portion touching the skin is reduced as much as possible. As a result, it is possible to suppress discomfort and a foreign object as much as possible due to contact with the second concave portion having a higher fiber density and higher rigidity than other portions.

With regard to the second concave portion of the present invention, from the height of the first side (in this case, the position closest to the second bottom) of the first concave portion on the side of the first surface (upper surface in this case) The size up to the height of the first surface of the bottom of the part depends on the thickness of the nonwoven fabric, but is preferably 0.05 to 2 mm, more preferably 0.075 to 1.5 mm, and more preferably 0.1 to 1 mm .

If the size from the height of the first surface of the first bottom portion of the first concave portion to the height of the first surface of the second bottom portion of the second concave portion is less than 0.05 mm, the fiber density becomes low at the time of forming the second bottom portion, And it is possible that the strength in the thickness direction of the nonwoven fabric is insufficient. On the other hand, when the thickness is more than 2 mm, when the second bottom portion is bonded to another member of the absorbent article, for example, an absorbent article or another nonwoven fabric, a film or the like, the peripheral wall portion of the second recess is excessively long, , There is a possibility of feeling hardness when compressed.

Regarding the relationship between the second concave portion and the convex portion, the size from the height of the first surface of the first bottom portion of the first concave portion to the height of the first surface of the second concave portion of the second concave portion, Is preferably 10 to 80% of the size from the height of the first surface of the bottom part (in this case, the position closest to the second bottom part) to the height of the first surface side of the top part of the convex part, more preferably 15 To 70%, and more preferably from 20 to 60%.

The size of the first concave portion from the height of the first surface side to the height of the first bottom surface portion of the second concave portion on the first surface side is larger than the height of the first bottom surface portion of the first concave portion from the height of the first surface side, If it is less than 10% of the height to the height of the first surface side, the space for forming the hole portion in the peripheral wall portion can not be sufficiently secured, so that the formation of the hole portion becomes insufficient and the flexibility as the convex portion and the nonwoven fabric can not be obtained. On the other hand, if it exceeds 80%, the second concave portion becomes excessively deep, the strength of the peripheral wall portion is lowered and the fluff easily occurs, so that the touch may be lowered.

The length of the second concave portion in the first direction and the second direction varies depending on the groove width of the groove portion, that is, the distance between adjacent convex portions, but is preferably 0.25 to 5 mm, more preferably 0.5 to 5 mm, 3 mm, and more preferably 0.75 to 2 mm.

If the length of the second concave portion in the first direction or the second direction is less than 0.25 mm, the second concave portion becomes excessively small and the formation of the second bottom portion becomes insufficient, so that the second concave portion may not function substantially. On the other hand, if it exceeds 5 mm, the second concave portion becomes excessively large, and there is a possibility that the uncomfortable feeling or foreign body feeling due to the concave portion may be easily felt on the skin.

The peripheral wall portion 17 includes a pair of first peripheral wall portions 19 and 19 formed along the first direction X and a pair of second peripheral wall portions 20 formed along the second direction Y And 20, respectively. The pair of first peripheral wall portions 19 and 19 are disposed at positions facing each other and the pair of second peripheral wall portions 20 and 20 are disposed at positions facing each other.

1 and 3, a pair of first peripheral wall portions 19 and 19 are provided with a hole portion 21 communicating from the inner space of the first recess portion 11 to the second surface 3, Respectively.

In this embodiment, the hole portion 21 is formed in each of the pair of first peripheral wall portions 19, 19, and these hole portions 21 are formed in the first peripheral wall portion 19 2 bottom portion 18 (therefore, there are two hole portions 21 in one second recess 16). On the other hand, a pair of the second peripheral wall portions 20 and 20 do not correspond to the hole portion 21, and the second peripheral wall portion 20 is directly connected to the second bottom portion 28.

In this embodiment, the hole portion 21 is formed in the first peripheral wall portion 19 because the groove portion 5 in which the hole portion 21 is formed and the portion of the fiber of the convex portion 4 adjacent thereto To release the tension. This makes it possible to improve the degree of freedom in which the fibers forming the whole of the convex portion 4 or the convex portion 4 move and the flexibility of the convex portion 4, (The direction from the first surface 2 to the second surface 3) and the flexibility in the first direction X and the second direction Y (particularly in the second direction Y) of the nonwoven fabric 1, The smoothness of the touch can be secured. As a result, the convex portion 4 is provided with an excellent soft feeling (excellent softness in the thickness direction) and a good sense of rough smoothening in the first direction X and the second direction Y (nonwoven fabric (Particularly excellent smoothness in the second direction Y) of the nonwoven fabric 1 can be imparted to the nonwoven fabric 1, and a superior feel and feel can be ensured throughout the nonwoven fabric 1, thereby achieving flexible touch.

Conversely, the reason for not forming the hole portion 21 in the second peripheral wall portion 20 is that the first direction X of the nonwoven fabric 1, that is, the direction in which the convex portion 4 and the groove portion 5 extend In order to ensure smoothness of the nonwoven fabric 1 in the first direction X when the skin slips, the step due to the presence of the second concave portion 16 is prevented from being caught on the skin. That is, since the second peripheral wall portion 20 is integrally connected to the first bottom portion 12 and the second bottom portion 18 continuously without seams, The skin is smoothly moved along the convex portion 4 or the groove portion 5 without much feeling of the step of the first bottom portion 12 due to the presence of the second concave portion 16 easy. This makes it possible to ensure the smoothness of the nonwoven fabric 1 in the first direction X, taking advantage of the flexibility of the convex portion 4 and the flexibility of the fibers.

The hole portion 21 is formed at a position near the second bottom portion 18 of the first peripheral wall portion 19 because the hole portion 21 is formed in the vicinity of the convex portion 4, 1 is as far as possible from the bottom part 12 so as to minimize the chance that the hole 21 touches the skin, thereby making it difficult to feel an uncomfortable feeling or foreign body feeling. Accordingly, it is possible to more reliably ensure smoothness when the skin slides in the plane direction of the nonwoven fabric 1. [

As shown in Fig. 3, the hole portion 21 is formed by melting the thermoplastic resin fibers contained in the nonwoven fabric 1, melting the thermoplastic resin fibers to form the peripheral edge portions 22 Respectively. The peripheral edge portion 22 of the hole 21 is provided with a rupture end 23a of the rupture fiber 23 having the rupture end 23a formed by breaking the thermoplastic resin fiber among the thermoplastic resin fibers ), And thermoplastic resin fibers cured by melting or the like are not included. The rupture end 23a of the rupture fiber 23 is a part of the thermoplastic resin fiber contained in the first rupture wall 19 and the thermoplastic resin fiber is stretched in the first direction X or physically cut Thereby breaking it. Therefore, as in the case where the thermoplastic resin fiber is melted, the broken fiber 23 is not rounded and rounded due to the melting of the fiber end, and the fiber is not hardened or hardened. The end is sharpened due to tearing, It became a mode in which little change occurred.

As a result, even if the skin touches the peripheral edge portion 22 of the hole portion 21, there is no thermoplastic resin fiber cured by melting in the peripheral edge portion 22, and therefore, The feeling of discomfort caused by the nonwoven fabric 1 is suppressed, and the feeling of hardness or roughness of the nonwoven fabric 1 is suppressed.

The inner space 21a of the hole 21 is formed with thermoplastic resin fibers 24 extending in the inner space 21a and a part of the broken fibers 23a extending in the inner space 21a, (23) are mixed, and the space is not completely opened. Thus, even if the skin touches the hole 21, since the thermoplastic resin fiber part of the hole 21 is partly extended or extended to the inner space 21a, the thermoplastic resin It is possible to reduce the boundary or step between the first peripheral wall portion 19 of the second concave portion 16 and the second bottom portion 18 and the hole portion 21 of the fiber. Thus, even when the hole 21 exists, the smooth touch can be maintained. Therefore, the difference in feeling caused by the presence of the hole 21 can be made as small as possible, and the feeling of discomfort when touching can be reduced.

The opening ratio of the internal space of the hole portion at this time is preferably 1 to 50%, more preferably 1.5 to 35%, and still more preferably 2.5 to 20%.

When the open area ratio of the inner space of the hole portion is less than 1%, the opening ratio is excessively low, so that the degree of freedom can not be imparted to the fibers of the convex portion and the convex portion, and sufficient flexibility of the convex portion can not be ensured. On the other hand, if the ratio exceeds 50%, the strength of the first peripheral wall portion having the hole portion tends to be low, and the boundary of the peripheral portion of the hole portion may be easily cured. However, the open area ratio of the inner space of the hole portion may be set to any value other than the above range or may be set arbitrarily, depending on the type and application of the absorbent article.

Regarding the size of the hole portion, the length of the maximum portion of the hole portion (in this embodiment, the length in the first direction) varies depending on the size of the second concave portion, but is preferably 0.25 to 5 mm Preferably 0.5 to 3 mm, and more preferably 0.75 to 2 mm.

If the length of the maximum portion of the hole portion is less than 0.25 mm, the formation of the hole portion is insufficient, the flexibility of the second concave portion can not be ensured, the tensile strength of the fiber of the convex portion is not lowered and sufficient flexibility of the convex portion can not be ensured . On the other hand, when the thickness exceeds 5 mm, the hole becomes excessively large, so that the fuzz easily occurs on the peripheral edge of the hole, and the feeling of uncomfortable feeling or foreign object due to the hole is likely to occur.

On the other hand, the maximum length in the height direction of the hole portion varies depending on the depth of the second concave portion, but is preferably 0.1 to 5 mm, more preferably 0.25 to 3 mm, and more preferably 0.5 to 2 mm will be.

If the maximum length in the height direction of the hole portion is less than 0.1 mm, the formation of the hole portion is insufficient. Even in this case, not only the flexibility of the second concave portion can not be secured but also the tensile strength of the fiber of the convex portion is not lowered Flexibility can not be ensured. On the other hand, if it exceeds 5 mm, the peripheral edge portion of the hole portion becomes excessively large, so that the nap is easily formed at the peripheral edge portion, and the hole portion tends to cause uncomfortable feeling and foreign body feeling.

The fiber 4b forming at least the convex portion 4 of the nonwoven fabric 1 has an average fiber diameter of 10 to 30 mu m.

In the present invention, the average fiber diameter of the fibers forming the convex portions is set to 10 to 30 占 퐉 in order to obtain delicate, soft and easy-to-skin feel when the skin of the fingers touches the convex portion, . The average fiber diameter of the fibers forming the convex portion is a very important factor for obtaining a nonwoven fabric which is delicate, soft and easy to be wound on the skin and which has a moist touch.

That is, according to the relationship between the distance (pitch) between the adjacent convex portions on the concave and convex portions of the surface of the object when the surface of the object is touched with the finger and the distance between adjacent projecting portions of the finger fingerprint, It is said that the surface of the object is rough and rough. That is, when the convex portion of the surface of the object enters between the protruding portions of the fingerprint, and a flat portion which is a recess portion between the protruding portions of the fingerprint or a side portion other than the tip of the protruding portion is stimulated, Delicate, soft and irregular texture can be obtained.

Generally, it is said that the distance between adjacent projections is about 460 +/- 15 mu m. Therefore, in the present invention, convex portions which are most likely to come into contact with the skin in the nonwoven fabric are formed by fibers having an average fiber diameter sufficiently smaller than the distance between adjacent protruding portions in the fingerprint, and the convex portions of the nonwoven fabric are contacted with fingers The fibers forming the convex portions were easily inserted between the protruding portions of the fingerprint.

More specifically, as shown in Fig. 4A, the human finger 30 has a plurality of protruding portions 31 and recessed flat portions 32 existing between these protruding portions 31 ). The average fiber diameter of the fibers 4b forming the convex portion 4 is smaller than the distance between the adjacent protruding portions 31 in the finger 30 when the protruding portion 4 is contacted by the finger 30 The fibers 4b forming the convex portion 4 enter between the adjacent protrusions 31 and 31 in the fingerprint of the finger 30 as shown in Fig. 4 (b).

As a result, a plurality of the fibers 4b forming the convex portion 4 come into contact with the flat portion 32 of the finger 30 or the side portion 31a of the protrusion 31, Since it stimulates the tactile organ, it is possible to obtain a delicate, soft and moist texture that is easily wrapped around the skin.

Here, if the average fiber diameter of the fibers forming the convex portion is less than 10 mu m, the volume of the nonwoven fabric is not only insufficient, but also tends to increase in the fiber density, so that flexibility may be impaired. Further, the overall strength of the nonwoven fabric is also lowered. On the other hand, if it exceeds 30 탆, it is considered that it is difficult to contact the adjacent protrusions in the fingerprint, particularly the flat portion, so that it is difficult to obtain a delicate sensation and a moist touch can not be obtained.

The average fiber diameter of the fibers forming the convex portions is more preferably 10 to 20 占 퐉.

The average fiber diameter of the fibers forming the convex portion can be measured by obtaining an enlarged image of the fiber forming the convex portion by an electron microscope or a microscope (for example, VHX-2000 manufactured by KEYENCE) By measuring the distance between them. The number of measurements is 100, and the average value is taken as the average fiber diameter.

In the nonwoven fabric 1, the average fiber-to-fiber distance of the fibers forming the convex portion 4 is 50 to 150 mu m.

In the present invention, it is preferable that the average fiber-to-fiber distance of the fibers forming the convex portions is 50 to 150 占 퐉 because the position of the fibers forming the convex portions is more easily adapted to the distance between the adjacent protruding portions in the fingerprint So that the fibers forming the convex portion are brought into contact with each other so as to follow the irregularities of the fingerprint as much as possible. As a result, the fibers can be inserted more stably and surely between the protrusions of the fingerprint fingerprint, so that when the protrusions are touched with the fingers, the skin is easily wound on the skin, and a moist feeling can be obtained more reliably and stably.

If the average fiber-to-fiber distance of the fibers forming the convex portions is less than 50 占 퐉, the distance between the fibers becomes too close to each other, and as a result, the fibers become difficult to move. Therefore, the fibers forming the convex portions are less likely to follow the irregularities of the fingerprint. On the other hand, if it exceeds 150 mu m, it is difficult for fibers forming the convex portion to enter between the adjacent protruding portions in the fingerprint fingerprint and also to reduce the number of fibers that can enter, so that it is difficult to obtain a delicate sensation, There is a possibility of damage.

The average fiber-to-fiber distance of the fibers forming the convex portions is more preferably 60 to 130 占 퐉, and still more preferably 70 to 110 占 퐉.

The average fiber-to-fiber distance of the fibers forming the convex portion can be measured using a mercury porosimeter (manufactured by Shimadzu Corporation) according to the mercury intrusion method (JISR 1655), for example. The mercury infiltration method is a method of mercury infiltration by measuring the pressure applied to mercury when the mercury is pressed into the constituent fibers of the nonwoven fabric to be measured and the volume of the mercury injected into the space between the constituent fibers of the nonwoven fabric, You can get information about the structure.

Specifically, the interfiber distance of the nonwoven fabric can be measured in the following order using a mercury porosimeter.

1) A sample for measurement is prepared by cutting the nonwoven fabric to be measured into 24 mm 15 mm. Three samples are prepared for this measurement.

2) The three measurement samples were set on a sample cell of a mercury porosimeter (manufactured by Shimadzu Corporation) so as not to overlap with each other, and then the pressure applied to the mercury was gradually changed, (I.e., the pore volume) of the mercury injected into the pores (pores). The measurement is carried out in an environment of 22 deg. C and 65% RH.

3) The pore diameter D (μm) of the pores (that is, the inter-fiber distance (μm) of the nonwoven fabric) is calculated according to the following formula (1), and the relationship between the pore diameter D and the pore volume D (derivative / integral curve). The various measuring conditions in the following equation (1) are: mercury surface tension of 0.483 N / m, contact angle of 130 deg., Mercury pressure of 0-414 MPa (absolute pressure).

(Where D is the hole diameter (inter-fiber distance),? Is the surface tension of mercury,? Is the contact angle, and P is the pressure.)

4) From the obtained distribution curve of the pore diameter D, the ratio of the volume of the pores having the pore diameter D of 50 to 150 mu m to the total volume of the pores having the pore diameter D of 0 to 500 mu m is calculated.

5) The above operations 2) to 4) are repeated three times, and the average value of the obtained volume ratios is defined as the ratio (%) of the total interfiber distance of 50 to 150 mu m.

As another method for measuring the average fiber-to-fiber distance of the fibers forming the convex portion, the following method can be used.

That is, the nonwoven fabric to be measured was cut into a quadrangular shape of 5 cm in each direction, and a 3D image connecting function of a microscope (VHX-2000 manufactured by KEYENCE, lens VH-Z20W opened) A 200x magnified image in which the focal points coincide with each other up to a depth of 100 mu m is obtained and the outer side of the fiber whose focal point coincides is extracted based on the enlarged image to make the surface formed thereon a fiber space. The area occupied by the fiber space is obtained by using the area measuring function of the microscope. At this time, an arbitrary place of the sample is arbitrarily selected, and the area of the fiber space in the selected range is measured at 100 points. (R) is obtained from the area A per one fiber space in the selected range (fiber space area (average value)) according to the following formula (2), and the fiber space diameter do.

The nonwoven fabric 1 has a gap between the tops 4a of the projections 4 and other projections 4 adjacent to the projections 4, (The pitch of the protrusions) between the tops 4a of the base 4 is 0.5 to 2 mm.

In the present invention, the distance between the top of the convex portion and the convex portion of the convex portion and the top portion of another convex portion adjacent to the convex portion is 0.5 to 2 mm when the finger touches the nonwoven fabric, Almost all of the protruding portions of the protruding portions are reliably brought into contact with the nonwoven fabric between the protruding portions and the protruding portions so that the side portions and the like of the protruding portions can be easily stimulated. The distance between the top of the convex portion and the convex portion and the top of another convex portion adjacent to the convex portion is obtained in addition to the average fiber diameter of the fibers forming the convex portion described above by obtaining a delicate and smooth non- This is a very important factor.

That is, whether or not a person who touches the nonwoven fabric with a finger touches the nonwoven fabric is delicate, smooth, and easily tends to be wrapped around the skin and feels a moist feeling, whether or not the side portion of the protrusion of the fingerprint is irritated is a problem. It is needless to say that the magnetic pole for the side surface portion of the protruding portion and the like is not limited to the case where the fibers forming the convex portion are sandwiched between the protruding portions of the fingerprint fingerprint. However, when the finger touches the nonwoven fabric, It can happen even if it touches.

When the finger touches the nonwoven fabric, the finger often enters between the convex portion and the convex portion as well as the convex portion. At that time, the protrusion portion of the fingerprint also enters between the convex portion and the convex portion, Etc.), the non-woven fabric can be stably and smoothly moistened with the skin, and a moist feeling can be stably obtained.

As described above, since the distance between the adjacent protrusions in the human fingerprint finger is about 460 +/- 15 mu m, the distance between the top of the protrusion and the top of the other protrusion adjacent to the protrusion is less than 0.5 mm , It is considered that the protruding portion of the fingerprint is difficult to enter between the convex portion and the convex portion and does not enter at all. If the distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion exceeds 2 mm, the protrusion of a plurality of the fingerprints can be inserted between the convex portion and the convex portion. However, The protruding portion of the fingerprint may be difficult to contact with the nonwoven fabric depending on the place, place, or the like. In this case, since there is a possibility that the protrusions of the fingerprint, especially the side portions of the protrusions, are weak or irritable, almost all of the protrusions between the protrusions and the protrusions can not be stimulated well, It is delicate and smooth, and it is easy to wind on the skin, so that a moist texture can not be obtained.

Therefore, in the present invention, the distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion is 0.5 to 2 mm.

Further, when the distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion is less than 0.5 mm, the distance between the top portion of the convex portion and the top portion of the adjacent convex portion is excessively short, And consequently the area of contact with the skin due to the convex portion can not be reduced so much that there is a possibility that the touch may be lowered.

On the contrary, when the distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion exceeds 2 mm, the distance between the top portion of the convex portion and the top portion of the adjacent convex portion is excessively large, There is a high possibility that the finger touches the first concave portion when the finger is touched, resulting in an increased chance of touching the second bottom portion of the second concave portion having a high fiber density and high rigidity, .

The distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion is measured in the following manner, for example.

Prepare a sharp cutter (for example, standard replacement blade HA-100NB for cutter knife HA-7NB (trade name) manufactured by Kokuyo Co., Ltd.) and cut the nonwoven fabric.

After leaving for 24 hours or more after the cutting, the cross section of the sheet is magnified 5 times by a microscope manufactured by Keith Co., and the distance along the Y axis direction between the apexes of adjacent convex portions is measured. At this time, when the vertex of the convex portion has a constant width in the Y-axis direction, measurement is performed with the center of the constant width in the Y-axis direction as the apex.

Then, the distance along the Y-axis direction between the apexes of adjacent convex portions is measured at 10 points, and the average value is defined as the distance between the apex portion of the convex portion and the apex portion of the other convex portion adjacent to the convex portion.

Hereinafter, a method for producing the nonwoven fabric 1 for absorbent article having the above-described structure will be described.

5 to 8 illustrate an example of a manufacturing apparatus for manufacturing the nonwoven fabric 1. The manufacturing apparatus 50 includes a nonwoven fabric 51 to be processed to be processed into a nonwoven fabric 1, (52) for unwinding the nonwoven fabric (51) to be processed toward the conveying direction (MD) and a preheating device (52) for preheating the nonwoven fabric (51) to be processed formed by the winding device 61). The nonwoven fabric 51 to be processed to which the preheating is applied is stretched to form the convex portion 4 and the groove portion 5 (including the first concave portion 11 and the second concave portion 16) And a shaping device 62 for performing a shaping process.

Examples of the method for producing the nonwoven fabric to be processed which is unwound by the unwinding device include a method of forming a web (fleece) and physically and chemically bonding the fibers together. Examples of the method of forming the web include a spunbond method , Dry method (card method, melt blow method, air laid method and the like), wet method and the like. Examples of the bonding method include thermal bond method, chemical bond method, needle punch method, stitch bond method, And the like.

The fibers used for the nonwoven fabric to be processed can be fibers having high opacity, particularly high whiteness, from the viewpoint of the concealing ability of the excreted liquid when used in the absorbent article. For example, even when an opaque light transmission inhibitor is used good. As the light transmission inhibitor, an inorganic filler can be exemplified. Examples of the inorganic filler include titanium oxide, calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, calcium sulfate, aluminum hydroxide, magnesium hydroxide, Alumina, mica, glass powder, shirasu balloon, zeolite, silicate clay and the like. These may be used in combination of two or more kinds. In particular, titanium dioxide is preferable in view of the processability and the like of a fiber production step.

As the thermoplastic resin fiber, additives such as an antioxidant, a light stabilizer, an ultraviolet absorber, a neutralizer, a nucleating agent, an epoxy stabilizer, a lubricant, an antibacterial agent, a flame retardant, an antistatic agent, a pigment and a plasticizer may be added as needed. The thermoplastic resin fiber is preferably subjected to hydrophilization treatment with a surfactant, a hydrophilic agent, or the like.

The basis weight of the nonwoven fabric to be processed is usually 10 to 100 g / m ² , preferably 15 to 75 g / m ² , and more preferably 20 to 50 g / m ² . The thickness of the nonwoven fabric to be processed is usually 0.1 to 5 mm, preferably 0.5 to 3 mm, and more preferably 0.8 to 2 mm.

In this embodiment, the preheating device 61 is provided with a pair of upper and lower heating rolls 61a and 61b. The preheating device 61 feeds the conveyed nonwoven fabric 51 to the lower heating roll 61b, And is conveyed to the heating roll 61a on the upper side which is rotating and heated by the heating roll 61a to heat the surface of the nonwoven fabric 51 to be processed which is not heated by the lower heating roll, .

6, the upper stretching rolls 63 are arranged at regular intervals in the roll width direction. The stretching rolls 63, Protruding ridges 63a formed in plural rows parallel to each other along the outer peripheral surface of the upper stretching roll 63 and plural rows of recesses 63b formed between the adjacent protruding ridges 63a and 63a.

On the other hand, the lower stretching roll 64 has a plurality of fins 64a provided on the outer peripheral surface thereof so as to be engaged with the groove 63b of the upper stretching roll 63 and a plurality of recesses 64b . 6, the fins 64a are arranged at regular intervals so as not to come into contact with the protruded ridgelines 63a of the upper stretching rolls 63 in the roll width direction, and at the same time, Are arranged substantially linearly at regular intervals along the outer circumferential surface. 7, the lower stretching roll 64 in this embodiment has a configuration in which a plurality of fins 64a are arranged in a staggered manner on the outer peripheral surface of the lower stretching roll 64 have.

When the manufacturing method of the nonwoven fabric 1 for absorbent articles is carried out using the manufacturing apparatus 50 having the above-described configuration, the preheating step of preheating the unwoven fabric 51 to be unwound from the unwinding device 52 And a shaping step of shaping the nonwoven fabric 51 to be processed through the preheating step and shaping the shaping step.

The preheating step is performed by winding the nonwoven fabric 51 to be processed which has been unwound from the unwinding device 52 and conveyed along the conveying direction MD to a pair of upper and lower heating rolls 61a and 61b rotating by the preheating device 61, The both surfaces of the sheet surface of the nonwoven fabric 51 to be processed are heated to apply preheating.

The preheating temperature varies depending on the kind of the thermoplastic resin fibers constituting the nonwoven fabric to be processed. For example, it is preferable to heat the thermoplastic resin fibers used for the nonwoven fabric to be processed to a temperature higher than the temperature at which the softening of the thermoplastic resin fibers starts, desirable.

When the preheating temperature is higher than the melting point, the thermoplastic resin fibers are dissolved and hardened, so that the soft touch is impaired. If the temperature is lower than the temperature at which softening of the thermoplastic resin fibers is started, bonding of the thermoplastic resin fibers is maintained, and it becomes difficult to form the nonwoven fabric to be processed in the subsequent molding step, and it becomes difficult to form appropriate irregularities. For example, in the case of a conjugate fiber of core sheath type of polyethylene terephthalate (PET) and high density polyethylene (HDPE), the temperature of the outer circumferential surface of the heating roll is preferably set to about 60 to 120 캜.

The shaping process is a process in which the nonwoven fabric 51 to be processed which has been conveyed through the preheating process is placed between upper and lower stretching rolls 63 and 64 which are rotated while being engaged in the shaping device 62, The nonwoven fabric 51 of the lower stretching roll 64 is sandwiched between the protruding ridges 63a and 63b of the upper stretching roll 63 and the recess 64b and the pin 64a of the lower stretching roll 64 It is formed by stretching. In addition, it is preferable to heat the nonwoven fabric 51 to be processed by heating the stretching rolls 63 and 64 so that the forming process can be easily performed. The heating temperature at this time is preferably higher than the preheating temperature in the preheating step and lower than the melting point temperature of the nonwoven fabric 51 to be processed.

The upper stretching roll 63 presses the portion of the projecting ridge 63a, which is in contact with the nonwoven fabric 51 to be processed, into the recess 64b of the lower stretching roll 64, As a result, the convex portion 4 is formed.

On the other hand, the lower stretching roll 64 has a plurality of fins 64a arranged in a line in the circumferential direction, and the nonwoven fabric 51 to be processed, which is in contact with the tip portion of the pin 64a, Into the same groove (63b) of the stretching roll (63). At this time, a portion of the nonwoven fabric 51 to be processed, which is tensioned in the groove 63b in a non-contact state with the pin 64a, becomes the groove portion 5. [ The portion of the pin 64a that has been in contact with the tip end portion of the pin 64a is strongly press-fitted into the groove 63b to form the protrusion 4 and the groove 5, A first peripheral wall 19 and a second peripheral wall 20 extending in the roll width direction and a second recess 16 having a second bottom 18 are formed.

As for the second bottom portion 18 of the second concave portion 16, when the upper stretching roll 63 and the lower stretching roll 64 are in contact with the nonwoven fabric 51 to be processed The tip end portion of the pin 64a is press-fitted into the groove 63b with the contact portion of the nonwoven fabric 51 of the object to be processed, so that the fiber density is substantially higher than the other portions and the rigidity is improved. Therefore, the rigidity of the entire nonwoven fabric 1 is improved by the action of the second bottom portion 18 of the second concave portion 16.

The portion of the nonwoven fabric 51 to be processed which was in contact with both ends in the width direction (roll width direction) of the tip end portion of the pin 64a is a portion where the protruded ridge 63a is located on the nonwoven fabric 51 The tensile force generated when press fitting in the direction of the lower stretching roll 64 is also held so that the pin 64a scrapes the thermoplastic resin fiber forming the first peripheral wall portion 19 or breaks the fiber, The breakable fibers 23 having the protruding portions 23a are formed.

The hole 21 having the peripheral edge portion 22 including the break end 23a of the broken fiber 23 is formed in the second recess 16. Some of the thermoplastic resin fibers remain in the state of spreading over the inner space 21a of the hole 21 (the thermoplastic resin fibers 24 that are spread), and some of the broken fibers 23 23a are extended into the inner space 21a.

Here, the formation of the hole portion 21 is effective in the direction along the conveyance direction MD of the nonwoven fabric 51 to be processed, that is, the direction along the rotation direction of the stretching rolls 63 and 64 The hole 21 is formed in a portion extending along the direction in which the convex portion 4 and the groove portion 5 are extended, Is formed in the peripheral wall portion (19).

The nonwoven fabric finished with the embossing process is completed as the nonwoven fabric 1 for the absorbent article by forming the convex portion 4 and the groove portion 5. The nonwoven fabric 1 is then used for a portion of the absorbent article such as a disposable diaper, a sanitary napkin, a urinary incontinence pad, a panty liner, or the like that comes into contact with the skin, And adhered to the outer surface.

Since the average fiber diameter of the fibers 4b forming the convex portion 4 is smaller than the distance between the adjacent protruding portions 31 in the fingerprint of the finger 30 The fibers 4b forming the convex portion 4 can be inserted between the protruding portions 31 and 31 adjacent to the fingerprint. The distance between the top 4a of the convex portion 4 of the nonwoven fabric 1 and the top 4a of the other convex portion 4 adjacent to the convex portion 4 and the distance between the top 4a of the convex portion 4, The entire convex portion 4 can easily follow the irregularities of the finger 30 and the fingerprint of the finger 30 by setting the average fiber distance of the fibers 4b forming the convex portion 4 to a predetermined range, The fibers 4b forming the finger 4 are more likely to enter the adjacent protrusions 31 and 31 in the fingerprint of the finger 30. [ In addition, the presence of the second recess 16 suppresses the area of the first bottom 12 of the first recess 11 contacting the skin, so that a soft touch can be obtained.

As a result, not only the soft touch of the whole nonwoven fabric 1 can be obtained but also the fibers 4b forming the convex portion 4 are formed in the flat portion 32 between the protruding portions 31 and 31 of the fingerprint fingerprint And stimulates the tactile organs in the side surface portion 31a of the protruding portion 31, so that a delicate soft touch and a smooth touch can be obtained.

Particularly, in the convex portion 4, the hole portion 21 of the first peripheral wall portion 19 of the peripheral wall portion 17 releases the tension of the fibers forming the adjacent convex portion 4, The flexibility of the convex portion 4 is improved because the flexibility of the entire or the fiber 4b forming the convex portion 4 is improved. Therefore, when the finger 30 touches the convex portion 4, not only the convex portion 4 is flexibly deformed by the external force to be fitted to the finger 30, but also the fibers forming the convex portion 4 The fibers 4b forming the convex portion 4 tend to follow the irregularities of the fingerprint of the finger 30 due to the height of the degree of freedom of the finger 4b. As a result, a delicate, smooth and smooth touch can be stably obtained.

The first peripheral wall portion 19 of the second concave portion 16 has the hole portion 21 which penetrates between the first surface 2 and the second surface 3, It is not necessary to form the hole.

Although the hole portion 21 is formed in the first peripheral wall portion 19 in the above embodiment, the hole portion may be formed in the pair of second peripheral wall portions formed along the second direction, Or may be formed on the peripheral wall portion.

In the above embodiment, the hole portion 21 is disposed near the second bottom portion 18 in the first peripheral wall portion 19. However, as for the position of the hole portion in the peripheral wall portion, And may be set arbitrarily within a range that does not impair the flexibility or rigidity of the nonwoven fabric.

In the above embodiment, the thermoplastic resin fibers 24 extending in the inner space 21a of the hole 21 are present, but the thermoplastic resin fibers spanning the inner space of the hole may not be present . Further, as in the above-described embodiment, the breaking end portion of the broken fiber need not extend into the inner space of the hole portion.

In the above embodiment, the second concave portion 16 is formed in a substantially rectangular parallelepiped shape. However, the shape of the second concave portion can be any shape such as a cylindrical shape or a prism shape.

In the above-described embodiment, the convex portion 4 continuously extends in the first direction X of the nonwoven fabric 1. However, the convex portion may not necessarily extend continuously in the first direction of the nonwoven fabric, or may be intermittent. However, at this time, it is preferable that the second concave portion is formed on the first bottom portion of the first concave portion sandwiched by the portion where the adjacent convex portions are continuous to each other, whereby the convex portion is likely to touch the skin first , On the contrary, it is difficult to contact with the second concave portion, so that the second concave portion makes it difficult to feel a foreign object or a sense of discomfort.

In the above embodiment, the fibers 4b forming the projections 4 of the nonwoven fabric 1 have an average fiber diameter of 10 to 30 mu m and an average fiber-to-fiber distance of 50 to 150 mu m. The fiber forming the other portion such as the groove portion can have the average fiber diameter or the average fiber-to-fiber distance range equivalent to the fiber forming the convex portion.

Example

In order to confirm the performance of the nonwoven fabric for absorbent articles according to the present invention, a comparative experiment was conducted using the nonwoven fabric according to the present invention (Example) and the nonwoven fabric having no constitution of the present invention (Comparative Example).

As a comparative experiment, when the subject touched the upper surface (surface on which the convex portion protrudes) of the sample of the nonwoven fabric with the finger along the longitudinal direction and the width direction of the sample with respect to the example and the comparative example, , "Smooth", "wobbly" or "guitar" were evaluated, and the results were compared.

In the sensory evaluation in this comparative experiment, "moist" refers to a feeling of feeling as if there is light moisture as if it is wrapped around the skin and is not actually damp, "smooth" refers to a smooth, rough, It is said that "to be wrinkled" means to distinguish each touch as touch feeling having no moisture and dry feeling. In addition, the touch of "moist" and the touch of "wobbly" were opposite to each other, and the "smooth" was a touch between those "moist" and "wobbly".

In this comparative experiment, two kinds of samples made of the nonwoven fabric according to the present invention (hereinafter referred to as Examples 1 and 2), three non-woven samples according to the present invention (hereinafter referred to as Comparative Examples 1 and 2 , Referred to as Comparative Example 3). This sample was obtained by cutting the nonwoven fabric to be tested into 100 mm x 100 mm.

The nonwoven fabric according to the present invention has basically the same constitution as that described in the above embodiment, and was manufactured by the same manufacturing method. In Examples 1 and 2, the distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion (pitch, hereinafter referred to as "distance between the convex portions") and the fiber forming the convex portion Have different average fiber diameters.

On the other hand, the nonwoven fabric of Comparative Example 1 corresponds to the nonwoven fabric to be processed used in the production of the nonwoven fabric according to the present invention in the above embodiment, . In the nonwoven fabric of Comparative Example 1, the average fiber diameter as a whole was equal to the average fiber diameter of the fibers forming the convex portions in Example 1. [

The nonwoven fabric according to the comparative example 2 is a concavo-convex type in which the cross section of the nonwoven fabric is formed by a pair of deformed rolls each having protruding ridges and grooves engaged with each other and having a substantially rectangular cross section. Regarding the manufacturing method of the nonwoven fabric according to Comparative Example 2, the elements other than the negative type are basically the same as those of the first and second embodiments. The average fiber diameter of the fibers forming the convex portion of the nonwoven fabric of Comparative Example 2 is the same as that of Example 1, but the structure of the nonwoven fabric and the distance between the convex portions are different from those of Example 1.

The nonwoven fabric of Comparative Example 3 has basically the same structure as that described in the above embodiment and was manufactured by the same manufacturing method. However, the average fiber diameter of the fibers forming the convex portion is not included in the scope of the present invention And the fibers constituting the nonwoven fabric are also different from those of the first and second embodiments. The distance between the convex portions of the comparative example 3 is the same as that of the first embodiment.

Regarding Example 1, Example 2, Comparative Example 1, and Comparative Example 2, a nonwoven fabric formed of PET / PE core sheath type conjugated fiber (basis weight 30 g / m ² ) was used and in Comparative Example 3 , And the nonwoven fabric is formed by PET / PP core sheath type conjugated fiber (basis weight 30 g / m ² ). Examples 1 and 2 and Comparative Examples 1 and 3 are both through-air nonwoven fabrics. In Examples 1 and 2 and Comparative Examples 2 and 3, the heating temperature was set to 100 ° C in the preheating process and the forming process, And was carried at a conveying speed of 250 m / min.

The distance between the convex portions and the average fiber diameter of the fibers forming the convex portions were measured by the measuring method described in the above embodiment.

The results of the comparative experiment are shown in the following table. In the table, "1" means "moist", 2 means "smooth", and 3 means "worse".

As can be seen from Table 1, with respect to Example 1, all of the subjects felt a feeling of "moist", and in Example 2, many people felt a feeling of "moist" No one felt the touch. However, in the comparison between Example 1 and Example 2, many people felt a feeling of "moist" in Example 1, because the distance between the convex portions in Example 2 was the upper limit of the range of the present invention , It is considered that the embodiment 1 in which the distance between the convex portions deviates from the upper limit value and the lower limit value of the range of the present invention is "moist".

On the other hand, regarding the comparative examples 1 to 3, all of the test subjects did not feel a feeling of "moist". As to Comparative Example 1, although the average fiber diameter is within the range of the present invention, the basic structure of the nonwoven fabric of the present invention (in this embodiment, the element relating to the basic shape of the nonwoven fabric That is, the structure of the nonwoven fabric having the convex portion, the first concave portion in the groove portion, and the second concave portion other than the average fiber diameter of the fibers), and therefore, .

In Comparative Example 2, since the base structure of the nonwoven fabric of the present invention was not provided, and the distance between the convex portions was outside the scope of the present invention, the average fiber diameter forming the convex portion of the nonwoven fabric having the concave- Even if it is in the scope of the invention, it is considered that "touching" means that the touch can not be obtained from the fact that the base structure of the nonwoven fabric of the present invention is not provided and the distance between the convex portions is not within the range of the present invention.

The comparative example 3 has the same basic structure as that of the present invention. However, since the average fiber diameter of the fibers forming the convex portion is out of the range of the present invention, it is considered that "moist" can not provide tactile sensation.

As described above, according to the nonwoven fabric for an absorbent article of the present invention, it has been proved that "touching" can obtain touch.

1: nonwoven fabric for absorbent articles
2: the first side of the nonwoven fabric
3: Second side of the nonwoven fabric
4: convex portion
4a: the top of the convex portion
5: Groove
11: first concave portion
12: first bottom portion
16: second concave portion
17:
18: second bottom portion
19: first peripheral wall portion
20: second peripheral wall portion
21:

Claims (9)

A plurality of convex portions having a first surface and a second surface opposite to the first surface and protruding from the second surface toward the direction of the first surface and a plurality of convex portions projecting from the first surface to the direction of the second surface The nonwoven fabric for absorbent articles according to any one of claims 1 to 3, wherein the nonwoven fabric comprises thermoplastic resin fibers,
Wherein the convex portion is formed to extend in a first direction in a plane direction of the nonwoven fabric and is formed at a predetermined interval in a second direction orthogonal to the first direction in a plane direction of the nonwoven fabric,
Wherein the groove portion is formed so as to extend toward the first direction in a space between the convex portions adjacent to each other in the second direction, and the groove portion is formed so as to extend in the direction of the second surface from the position of the first surface in the top portion of the convex portion And a second recess formed in the first recess and formed in a recessed shape discontinuously in the first direction and opened in the first recess in the first recess, And a plurality of second recesses having a second bottom portion located in the direction of the second surface,
The distance between the top of the convex portion and the top of another convex portion adjacent to the convex portion is 0.5 to 2 mm,
Wherein the fibers forming at least the convex portion of the nonwoven fabric have an average fiber diameter of 10 to 30 占 퐉. The nonwoven fabric for an absorbent article according to claim 1, wherein the fibers forming the convex portions have an average fiber-to-fiber distance of 50 to 150 탆. 3. The apparatus according to claim 1 or 2, wherein the second concave portion includes: a circumferential wall portion extending in a direction opposite to a direction in which the convex portion protrudes from the first bottom portion; And a second bottom portion formed so as to close the end portion at an opposite end thereof. The method according to claim 3, wherein the peripheral wall portion of the second recess has a pair of first peripheral wall portions formed along the first direction and a pair of second peripheral wall portions formed along the second direction, Wherein the first peripheral wall portion has a hole portion that penetrates between the first surface and the second surface. 5. The thermoplastic resin fiber according to claim 4, wherein the hole portion has a peripheral edge portion formed without melting the thermoplastic resin fiber, and the peripheries of the thermoplastic resin fibers are provided with a rupture end portion formed by rupture, And a nonwoven fabric for absorbent articles. The nonwoven fabric for an absorbent article as set forth in claim 4, wherein the hole portion has a part of the thermoplastic resin fiber in an inner space of the hole portion. 7. The nonwoven fabric for an absorbent article according to claim 6, wherein the hole portion has an opening ratio of 1 to 50%. The nonwoven fabric for an absorbent article as set forth in claim 4, wherein the hole portion is formed only at a position near the second bottom portion of the first peripheral wall portion. The absorbent article as set forth in claim 1 or 2, wherein the second concave portion has a distance from the first surface of the first bottom portion to the first surface of the second bottom portion in the first concave portion is 0.05 to 2 mm For nonwoven fabrics.

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